1. Field of the Invention
The present invention relates in general to a technique for designing a product, and more particularly to a technique effective to reduce a time required for designing a product.
2. Discussion of the Related Art
A product to be manufactured may be designed in a plurality of designing processes, which include a preliminary designing process wherein a geometry of a product is designed, and a subsequent designing process wherein a geometry of an object associated with the product in question is designed on the basis of the geometry of the product designed in the preliminary designing process. Where a part or component of a motor vehicle body is produced by pressing using a die set, for example, a body designing process 100, a part designing process 102 and a die set designing process 104 are sequentially performed in the order of description, as illustrated in FIG. 9. In the body designing process 100, an outer geometry of the vehicle body as a whole is designed. In the next part designing process 102, a part of the vehicle body is designed as an end product. In the last die set designing process 104, a geometry of a die set used for pressing a blank into the part is designed.
In the field of product designing, there is a strong need to reduce the required designing time. To meet such a need, there has been proposed a product designing system using a solid modeller, as disclosed in JP-A-7-49967, the subject matter of which is disclosed in U.S. patent application Ser. No. 08/286,570, one of the assignees of which is the assignee of the present application. This product designing system includes a preliminary designing process wherein cross sectional shapes and attributes for defining the geometry of a product to be manufactured are specified by an operator of the system, and a subsequent designing process in which the solid modeller is operated to automatically generate a solid model representative of the geometry of the product.
In the known product designing system indicated above, the subsequent designing process cannot be initiated until the preliminary designing process is completed. Therefore, where the designing procedure associated with a product includes a plurality of designing processes, the known product designing system has a limitation in its capability to reduce the required overall designing time.
Since the known product designing system is adapted to initiate the subsequent designing process after all items of designing information are finally determined in the preliminary designing process, the initiation of the subsequent designing process before the completion of the preliminary designing process would cause problems such as: requirement for considerable re-designing or correction of the product geometry in the subsequent designing process, in the event of some subsequent change of the designing information in the preliminary designing step; consequent increase in the designing time required for the subsequent designing process; and a risk of inaccuracy of design change in the subsequent process according to the change of the designing information in the preliminary process, and eventual product designing error due to incomplete or erroneous correction of geometry data in the subsequent designing process.
The required overall designing time may be reduced if computer-aided-design (CAD) systems used for the respective different designing processes have similar specifications following a common design concept which facilitates comparatively easier data communications between the different designing processes.
However, the use of such CAD systems having similar specifications based on a common design concept is actually difficult, since the functions to be performed by the individual CAD systems are different from each other, and therefore the CAD systems are not usually permitted to have similar specifications. Further, some existing product designing equipment includes CAD systems which have different specifications. In this case, modification of the systems so as to have similar specifications requires a lot of cost and time.